7. Kastawei Island, Vanuatu
Vanuatu is a small country located in the South Pacific. Kastawei Island that belongs to Vanuatu is a wonderful place for those who prefer active lifestyle. Here you can practice your skills in swimming and diving. It gives a lot of other opportunities as well. The territory of the island does not exceed one acre and covers only 0.83 acres, however it is quite enough to start building the home of your dreams. The island is sold for $199,000 USD which makes the site one of the cheapest islands available to potential buyers.